You know the story. Hirsute Aussie fresh off the boat conquers literary London armed only with a high-decibel shirt and a facility for larrikin wisecracks. Clive James never tires of telling it and, mostly, he seems to hope, we will never tire of reading it. Thus, 16 years on from his third volume of Unreliable Memoirs, James voyages again around his most vivid creation: his youthful self. He is a little older - this instalment gets him through Footlights fringe shows and, via Grub Street, to The Observer's television column and the emergence of Saturday Night Clive - but happily not much wiser.

It is becoming a curiously circular journey of discovery. Along the way, the book traces that odd phase of James's career when he seemed most weeks to be writing long narrative poems about the travails of young hopefuls in media land. (He will, you imagine, go down among many other things, as the last hack to get terza rima on to the front page of a newspaper.) He seems to see his life in similar terms to those of his verse-heroes, a rakish pilgrim's progress through the capital's society, never losing sight of the goal of fame or its price.

All writers are competitive, but few take that quality to such comic extremes as James. Even his self-deprecation is a kind of fighting talk; for all of his book's concentration on its author's failings - his early-hours work habits, his queasily roving eye, his habit of taking himself off to bed at the first sign of failure - he never quite wants you to forget that he has been a towering success in more than one field. Moreover, he presents this case so unashamedly, and carries it off with such fizz, that most of the time it seems like a virtue.

This spirit of one-upmanship invades every aspect of his recollections. The joints he smokes are bigger than anyone else's joints (there is a hilarious reminiscence of the stoned Clive trying to quote Cocteau); the friends that he hangs out with are funnier than anyone else's friends; and - he doesn't mind suggesting - his gift for phrasemaking is sharper than anyone else's gift. He fondly recalls some of his greatest hits - Arnold Schwarzenegger, as 'a brown condom full of walnuts' - and you wonder if that phrase has settled in the public mind in part because it seems to describe James's own method with sentences and paragraphs, each one full to bursting with nuggety little gags and bon mots.

Sometimes, there is a sanctimonious quality to this display. He ends his book with a swipe at younger writers from the Modern Review, now themselves cultural fixtures, who once carped at a London literary mafia: 'The intelligent and the talented always look like a mafia for the simple reason that they value each other's friendship,' he writes of himself and his mates. 'In time, the new guard learned that the only road to the top was the one on which the goods are delivered.'

There are few more engaging voices than James's when he is bursting the soaring dirigibles of his own or others' dreams; no one else, say, could quite describe the terrors of a failing theatre show in these terms: 'I counted the house like the quartermaster at Rorke's Drift counting cartridges.' When he leaves his vanity unpricked, however, it can start to sound like a different kind of celebrity reminiscence entirely.

During his television days, James would characteristically appear with a bank of television screens behind him. This multiple image of mini-Clives, each one squinting at the autocue, always seemed telling about a presenter who, not content with being a brilliant literary essayist, wanted rather to be a poet and, dissatisfied with writing as well as anyone ever had been about dire television, allowed himself to spend interminable prime-time nights in the company of Margarita Pracatan.

Clive James, as the New Yorker once had it, is a great bunch of guys; North Face of Soho introduces us to yet another Clive, while you guess that the man himself slips slightly further from view.